Method and apparatus of digitizing analog records

ABSTRACT

An analogue chart or record obtained from an automatic analyzer is positioned on a record-reading panel structure and a probe electrode is manually pushed through the chart at a desired position thereon, for example, at the peak of a curve, so as electrically to contact an underlying one of a number of mutually separated electrical contact strips. Individual conductors extend from all such strips to a decoding unit which provides a multidigit decimal identification of the strip which is contacted by the probe electrode. The decoding unit is in turn coupled to a coding unit in which the decimal digits identifying the actuated strip are converted into a binary coded decimal form for subsequent sequential recording in a tape punch unit to provide an output in a form suitable for further processing in an offline digital computer.

United States Patent Slutsky [451 June 20, 1972 [54] METHOD AND APPARATUS OF DIGITIZING ANALOG RECORDS [72] Inventor: Arthur Samuel Slutsky, S55 Shepherd Avenue West, Downsview 473, Ontario, Canada [22] Filed: Aug. 24, 1970 [21] Appl. No.: 66,538

SAMPLES 2 7 FOR TES TING RE CORD- DECODING UNI T 3,399,401 8/1968 Ellis et a1 ..340/347 AD Primary Examiner-Daryl W. Cook Attorney-Ame I. Fors and Frank I. Piper [57] ABSTRACT An analogue chart or record obtained from an automatic analyzer is positioned on a record-reading panel structure and a probe electrode is manually pushed through the chart at a desired position thereon, for example, at the peak of a curve, so as electrically to contact an underlying one of a number of mutually separated electrical contact strips. Individual conductors extend from all such strips to a decoding unit which provides a multi-digit decimal identification of the strip which is contacted by the probe electrode. The decoding unit is in turn coupled to a coding unit in which the decimal digits identifying the actuated strip are converted into a binary coded decimal form for subsequent sequential recording in a tape punch unit to provide an output in a form suitable for further processing in an off-line digital computer.

17 Claims, 6 Drawing Figures POWER 54 UNIT DISPLAY UNI T 52 TAPE '00! H READING STATION/33 l DIGITAL COMPUTER TEST RESULTS Patented June 20, 1972 4 Sheets-Sheet 1 INVENTOR.

ARTHUR S. SLUTSKY AGENT Patented June 20, 1972 3,671,716

4 Sheets-Sheet 5 PANEL BOARD FOR 000 NUMBERED srR/Ps 031' to '059' PANEL BOARD FOR ODD NUMBERED STRIPS 09/ to I19 INVENTOR:

-' ARTHUR S. SLUTSKY AGENT Patented June 20, 1972 4 Shets-Sheet 4 m mm m mm m mm m mm m mm Ymm m mm w mm 7mm s mm lN VENTOR: ARTHUR s. SLUTSKY 5% W AGENT METHOD AND APPARATUS F DIGI'IIZING ANALOG RECORDS BACKGROUND OF THE INVENTION The present invention relates to panel structures for use in a digitizing and record-reading system and to digitizing and record-reading systems incorporating such panel structures, as well as to a method for providing a digitized output signal indicative of a value of an analogue record.

Research and control laboratories frequently make use of devices, as exemplified by automatic analyzers, which provide analogue output data in the form of records, charts and the like, which records are subsequently measured, read or otherwise evaluated, to provide the value or values of the parameters being measured. Such subsequent evaluation of analogue records is not onlytime-consuming but is frequently a somewhat tiresome, tedious and boring task. Consequently, such evaluations are a frequent source of errors in many laboratory operations.

Many proposals have heretofore been made for facilitating the evaluation of such analogue records. It has, for instance, been proposed to couple equipment such as automatic analyzers directly to a digital computer, means being provided, of course, to convert the analogue output from such automatic analyzers into a digital form suitable for processing by the computer. Such a system is illustrated by considering the case in which an automatic analyzer is coupled to a conventional chart recorder having a stylus mounted for movement in the direction of the chart y-axis and adapted to print a trace on the chart which moves through the recorder in the direction of its x-axis. In such a case, the movement of the stylus as caused by changes in the analogue output of the automatic analyzer is automatically measured in the form of pulses which are counted and the resulting count is automatically converted into a form suitable for further processing by the on-line digital computer. Such on-line computer systems present the serious disadvantage that they require a permanent computer installation or at least computer availability at all such times as the automatic analyzer is operated. These requirements are inevitably very expensive and, therefore, totally preclude the adoption of such on-line computer systems by many laboratories.

An alternative approach has been to rely on the use of offline computers. In such a system, analogue data, for example, from an automatic analyzer are first recorded in a conventional manner and the records or charts so obtained are then read and the readings converted into a recordable digitized form for subsequent processing of the digital data of such records by an off-line computer which might, for example, be available on a time-sharing basis. Considering, for example, the case where an automatic analyzer is coupled to a chart recorder to provide a chart or record including one or more traces, digitizers or record-reading devices have heretofore been proposed for reading" such charts or records to provide digital output signal records which can then be further processed by a digital computer available on such a sharedtime basis. Such digitizers can, for example, be used to provide a punched-tape record of selected peaks from a chart obtained from a chart recorder. Such punched tapes are then fed to the digital computer in which their data are processed to provide a printed numerical output of the values of the desired parameters of the samples which were analyzed in the automatic analyzer.

This previously proposed adoption of the additional steps of digitizing and recording the data of analogue records has the very important advantages not only of avoiding the need for an on-line computer but also of reducing the risk of the aforementioned errors involved in the manual evaluation of analogue records. Furthermore, when such an additional step of digitizing is carried out manually, the operator retains the freedom to identify deviations and errors and to edit the results accordingly.

Digitizers of the type in question and as heretofore proposed have, however, presented serious disadvantages. Many such previously proposed record-reading digitizers have been both extremely expensive and complex in their constructions. Some previously known record-reading digitizers have also been very susceptible to error due to seemingly trivial factors such as variations in the voltage of the electrical supply from which they are energized, or they have included expensive and complex systems for avoiding such operational errors. For example, the use of one such previously known recordreading digitizer involves the manual positioning of a probe over the surface of an analogue chart supported on a resistive metal plate, the probe being pushed through the chart so as to contact the plate at a position corresponding to a desired position on the chart, such position then being identified by measuring the voltage existing between the probe and a reference position on the resistive plate. Other known digitizers of the type in question have involved the movement of cross-hairs over the analogue chart, the selected position thereon then being indicated by the operation of potentiometers coupled to carriages travelling on mutually perpendicular guideways and carrying arms on which such cross-hairs are mounted.

These known record-reading digitizers for use with off-line digital computers in the manner hereinbefore considered have all involved the measurement of at least one continuous parameter for identifying a desired position on a chart and have, therefore, been susceptible to error on variation of factors, such as the line supply voltage, which affect their operation. Ensuring adequate response linearity and stability of response is another problem with many known record-reading digitizers.

It is accordingly a principal object of this invention to provide a digitizing and record-reading system which is notonly relatively inexpensive but which is also free of the aforementioned susceptibility to errors due to factors such as variations in the line supply voltage.

Another object of this invention is to provide a digitizing and record-reading system which is simple in its construction, exceedingly simple and reliable in its operation, and susceptible to variation and modification to suit different operational requirements.

Yet another object of this invention is to provide a digitizing and record-reading panel structure by which an analogue record or chart may be received for processing in accordance with this invention.

A further object of this invention is to provide a novel method for the processing of analogue records.

Other objects of this invention will become apparent as the description herein proceeds.

SUMMARY OF THE INVENTION The present invention provides a digitizing and record-reading system intended for use in the aforementioned procedure of providing a digitized record from an analogue record, which digitized record can then be processed in an off-line digital computer.

The present invention differs from the previously proposed use of digitizing devices for such a purpose in that the digitization of the analogue record is effected in a discontinuous manner, i.e., in discrete steps, rather than by the identification of a position on the analogue record by the measurement of a digitizable value of a continuous parameter.

In its broadest scope, the method of this invention comprises the steps of disposing said analogue record in a predetermined position on a record-receiving panel structure including a plurality of individual and separate probe-actuable elements, each of which has an actuated and a non-actuated condition; applying a probe to said analogue record at a desired position thereon to actuate a corresponding and individual one of said probe-actuable elements to cause said corresponding individual one of said probe-actuable elements to adopt said actuated condition thereof; and identifying said corresponding individual one of said probe-actuable elements by virtue of said actuated condition thereof.

The present invention also embraces a record-reading and digitizing system for providing a digitized output signal indicative of a value of an analogue record, which system comprises a record-receiving panel structure for receiving said analogue record in a predetermined position thereon and including in turn a plurality of mutually isolated probe-actuable elements, each of which can have an actuated or a non-actuated condition; a probe adapted manually to be applied to said analogue record on said record-receiving panel structure in said predetermined position thereon to cause actuation of an underlying and individual one of said probe-actuable elements; a decoding unit adapted to provide a digitized output signal indicative of the identity of an instantaneously actuated one of said probe-actuable elements on manual application to said analogue record of said probe; and a plurality of signal transfer means extending from individual ones of said probeactuable elements to said decoding unit.

Novel record-receiving panel structures for use in the method and system of this invention also fall within its scope. Such a record-receiving panel structure is broadly defined as being a panel structure comprising a plurality of probe-actuable elements individually separated by probe-inert elements and including a record-receiving surface, means for maintaining an analogue record in a predetermined position on said panel structure.

Other features and advantages of the invention will become apparent as the description herein proceeds.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described merely by way of illustration with reference to the accompanying drawings in which:

FIG. l is a fragmentary perspective view of one embodiment of a novel record-receiving panel structure in accordance with this invention;

FIG. 2 is a vertical sectional view through a record-reading station incorporating the record-receiving panel structure of FIG. I and showing an analogue record or chart disposed thereon;

FIG. 3 is a schematic block diagram illustrating one embodiment of the system and method of the invention for the reading of an analogue record to provide both a visual display and a punched tape digital output record, and additionally showing the manner in which such a system can be used in conjunction with an automatic analyzer and an off-line digital computer;

FIG. 48 is a schematic and fragmentary diagram illustrating in greater detail one suitable construction for one panel board of the decoding unit utilized in the system shown in FIG. 3;

FIG. 5 is a schematic and fragmentary diagram illustrating in greater detail one suitable construction for one of three coding units utilized in the system shown in FIG. 3; and

FIG. 6 is a transverse vertical sectional view through one alternative construction for a record-receiving panel structure in accordance with this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Before describing the overall system shown schematically in FIG. 3 of the accompanying drawings, the record-reading station forming an important part of that system and a recordreceiving panel structure incorporated in that station will first be described with particular reference to FIGS. l and 2 of the accompanying drawings.

The panel generally indicated at 10 in FIGS. 1 and 2 of the accompanying drawings is formed from a plurality of alternate electrically conductive metal strips or elements ill and electrically insulating strips or elements 112. The strips 111 and 12 are maintained in their stacked assembled disposition as shown in FIG. 1 by electrically insulating rods 13 and M which are terminally threaded to receive washers l5 and nuts 16 which firmly clamp the strips Ill and f2 together. The top edge surfaces 117 of the electrically insulating strips 12 define a record sheet-receiving or supporting surface generally indicated at 119 while the top edge surfaces 20 of the electrically conductive metal strips lit are disposed downwardly of the record-receiving surface 19 for a reason which will be more readily understood as the description herein proceeds.

In accordance with another useful feature of this invention, the metal strips it are longer in the transverse direction relative to the panel 10 than are the insulating strips 12 so that they project from one side of the panel 10 to facilitate the connection thereto of individual connectors or wires which are collectively indicated at 211 and which extend to a decoding unit generally indicated at 34 and yet to be described.

The record-receiving panel structure is shown merely by way of example in FIG. 2 of the accompanying drawings as being supported at a record-reading station generally indicated at 33 by a frame generally indicated at 22 of any appropriate construction and as being provided with a lower edge flange 23 and an upper edge flange 2 providing transversely extending record-receiving slots into which a chart or record generally indicated at 26 can be inserted so as to be retained in a predetermined position on the panel structure 110.

The record-reading system in accordance with this invention also includes a manually operable probe generally indicated at 27 and which is shown in FIG. 2 as including a bandle 28 and a center electrode 29 electrically connected to an electrical lead 30.

It will now be understood that, having positioned a chart or record, such as chart 2b, in a predetermined position on the panel structure 10, i.e., by inserting such a record into the slots formed by the flanges 23 and 24, any desired position on the chart 26 can be identified by applying the probe electrode 29 of the probe 27 manually to the chart 26 so as to pierce the chart and to provide electrical connection between the probe lead 30 and an underlying and individual one of the metal strips or elements 111.

It will further be understood that, by assembling the panel structure 10 so that the top edge surfaces 20 of the metal strips llll are disposed below the record-supporting surface 19 constituted by the top edge surfaces W of the insulating strips 12, the use of the probe 27 in the manner already described will result in actual perforation or piercing of the chart 26 so providing a positive indication to an operator that an individual point on the chart 26 has been entered into the system.

Before describing one typical system which can be adopted for identifying which one of the strips ill has been actuated in the described manner by the probe electrode 29, it should perhaps be stressed that the invention is in no way restricted to the relative dimensions for the strips Ill and 12 as actually shown in the drawings and that, when used herein with reference to the action of the probe 27 on the panel structure T0, the term actuation is intended to embrace any appropriate coaction between a probe and such a panel structure.

With reference to the relative dimensions of the strips 11 and 12 of the panel structure 10 shown in FIGS. l and 2, it can perhaps usefully be indicated that a particularly effective panel for use in the reading of graphical records obtained from an automatic analyzer used in a hospital laboratory for the analysis of blood and urine samples was constructed with the metal strips llll each having a thickness of about 0.035 inch and with the insulating strips 112 formed of nylon and each having a thickness of about 0.030 inch. In applications where a greater or lesser degree of resolution is required, thinner or thicker strips can, however, be used.

As already explained, the panel structures of this invention differ from those of previously known record-reading digitizers in which the position of a probe, stylus or indicator is determined by measurement of a continuously variable parameter. In distinction, the identification of the position at which the probe 2'7 is applied to the record 26 is determined in accordance with this invention, in separate or discrete steps. This has a particularly important practical advantage in that the use of the panel structure 10 is independent of many factors, such as variation in the supply voltage, which frequently lead to inaccuracies in the use of previously known recordreading digitizers. The invention is free of such errors since means yet to be described are provided to indicate which one of the strips 11 is actuated by the probe 27 at any particular time and since no variations in the supply voltage will change the identity of such a particular one of the strips 11.

One typical system for identifying which of the strips 11 of the panel structure 10 is actuated at any particular instance will now be described in greater detail with reference to the overall record-reading and digitizing system shown in FIG. 3 of the accompanying drawings.

The overall system is shown in FIG. 3 as being used for reading analogue records or charts 26 obtained from a conventional chart recorder 31 coupled to an automatic analyzer 32 which is in turn operative to analyze test samples such as urine and blood samples as conventionally analyzed in large numbeta in clinical laboratories.

A chart 26 from the chart recorder 31 passes to a recordreading station generally indicated at 33. To simplify the ensuing description herein, the panel structure 10 as shown in FIGS. 1 and 2 and forming an important part of the recordreading station 33 will be assumed to be made up of one hundred and eighty of the metal strips 11, which strips will be individually referred to herein by appropriate consecutive three digit numbers, stripl being considered to be the lowermost one of the strips 11 on the panel structure 10 as shown in FIG. 3 and strip 180 being considered to be the uppermost one of the strips 11 as shown in FIG. 3.

The strips 001 to 180 are individually connected by the wires collectively indicated at 21 to the decoding unit indicated generally at 34 and which is provided with 22 electrical output conductors collectively indicated at 35, 36 and 37 and corresponding respectively to the hundreds digits 0 and 1, to the tens digits 0 to 9 and to the units digits 0 to 9 respectively.

The three sets of conductors 35, 36 and 37 extend from the decoding unit 34 to coding units 39, 40 and 41 respectively which are operative to provide binary coded outputs corresponding to respective ones of the decimal digits. Binary coded decimal output lines 42, 43 and 44 extend from the coding units 39, 40 and 41 respectively to separate shift registers 45, 46 and 47 respectively while separate sets of lines 48, 49 and 50 connect the output lines 42, 43 and 44 respectively to a three digit numerical visual display unit generally indicated at 51 and of any conventional type. Typical constructions for the decoding unit 34 and for the three coding units 39, 40 and 41 will be described in greater detail hereinafter with reference to FIGS. 4 and of the accompanying drawings.

The individual decimal digit shift registers 45, 46 and 47 are coupled together and through an output line 52 to a main logic unit generally indicated at 53 which is of any conventional type and which is energized from a main power unit indicated schematically at 54. The main logic unit 53 is also coupled by a line 55 to a tape punch unit generally indicated at 56.

Although any conventional equipment can be utilized in the main logic unit 53, it might usefully be noted at this juncture that the main logic unit 53 is shown in FIG. 3 as being coupled by line 58 to the shift register 47 so that a counter/controller within that main logic unit 53 is operative to transfer binary coded decimal digits from the shift registers 45, 46 and 47 sequentially to that main logic unit 53 for sequential transfer therefrom to the tape punch unit 56 for sequential recording thereby. For example, such a counter/controller can be designed first to cause the transfer of a binary coded decimal digit from the shift register 45 to the main logic unit 53 with transfer of the tens and units binary coded decimal digits from the shift registers 46 and 47 respectively to the shift registers 45 and 46 respectively. The counter/controller is next operative to transfer the binary coded decimal tens digit from the shift register 45 to the main logic unit 53 and to transfer the binary coded units digit from the shift register 46 to the shift register 45. Finally, the counter/controller causes the binary coded units decimal digit to be transferred from the shift register 45 to the main logic unit 53. The invention is, however, in no way restricted to the use of any particular hardware for the production of digital records of the data supplied to the shift registers 45, 46 and 47. Accordingly, the construction of the units 45, 46, 47, 53 and 56 will not be described in further detail herein.

To complete the general description of the system illustrated in FIG. 3, it can be noted that the digital record 62 provided by the tape punch unit 56 is indicated schematically by broken lines 63 as being fed to a digital computer indicated schematically at 64. The digital computer 64 is programmed to perform a required operation on the data fed thereto and to provide an output indicative of a desired parameter of the corresponding sample analyzed by the automatic analyzer 32.

The manner in which the computer 64 is programmed does not in itself form an essential feature of this invention but, in accordance with a particularly useful feature of this invention, the program for the computer 64 may be designed to accommodate variable operating parameters of the automatic analyzer 32. For example, interaction or carry-over between the individual samples evaluated by the analyzer 32 will, in some circumstances, vary in accordance with the speed at which that analyzer is operated and, in such a case, the program for the computer 64 can usefully be modified to accommodate such variations and to provide an automatic correction of the results. Such coupling of the analyzer 32 and the computer 64 is indicated schematically in FIG. 3 by the broken line 65. The results obtained by the application of this particular feature of the invention will be reported subsequently herein.

Referring now to FIG. 4 of the accompanying drawings, there is shown therein one panel board 70 of a total of 12 such panel boards which constitute the hereinbefore mentioned decoding unit 34. The panel board 70 is connected by 15 of the aforementioned wires collectively indicated at 21 to 15 of the metal strips 11 of the panel structure 10 provided at the record-reading station 33. The particular ones of the strips 11 to which the panel board 70 is connected are those indicated by the odd-numbered three-digit legends 061 to 089 at the left hand side of FIG. 4. Since all the strips 11 decoded by the panel board 70 are within the number range 061 to 089, a single output line indicated at 35-0 for the hundreds digit 0 extends from the panel board 70 to the hundreds digits coding unit 39. The tens digits output lines namely lines 36-6, 36-7 and 36-8 for the 6, 7 and 8 tens digits respectively extend from the panel board 70 to the tens' digits coding unit 40. Similarly, five units digits output lines namely lines 37-1, 37-3, 37-5, 37-7 and 37-9 extend from the panel board 70 to the units digits coding unit 41.

Three blocks 71, 72 and 73, each having five diodes, are individually connected to the lines 21 from the strips 11 with odd numbers of from 061 to 069, all the diodes of the first block 71 being connected to the aforementioned line 35-0, all the diodes of the second block 72 being connected to the aforementioned line 36-6 and the diodes of the third block 73 being connected to respective ones of the lines 37-1, 37-3, 37-5, 37-7 and 37-9. Similarly, three blocks 74, 75 and 76 each of five diodes are connected in the same way between the lines 21 from the strips 11 with odd numbers of from 071 to 079 and the lines 35-0, 36-7 and 37-1, 37-3, 37-5, 37-7 and 37-9 while blocks 77, 78 and 79 of diodes provide corresponding connections for the lines 21 from the strips 11 with odd numbers of from 081' to 089.

In the particular system illustrated in FIG. 3, the probe electrode 29 is adapted either to ground the one of the strips 11 with which it is in contact at any time or alternatively to apply a negative potential thereto. The effect of this is to permit current flow from the coding units 39, 40 and 41 to respective ones of the diodes in the panel boards of the decoding unit 34.

To simplify understanding of the operating mechanism, the situation where the metal strip 11 numbered 949 is actuated by the probe electrode 29 carrying a negative potential will now be considered in detail. In such a circumstance, a negative voltage will be applied to that one of the lines 21 which is connected to the 1169 numbered one of the strips 11. As a result, current will flow through the diodes 71-1969, 72-1169 and 73-069 from the lines 35-41, 36-4 and 37-9 as will readily be understood from FIG. 4.

It will now be understood that the decoding unit 34 is thus effective to allow current flow from individual ones of the lines 35, 36 and 37 from the coding units 39, 49 and 41 respectively, which individual lines correspond to the number of the strip actuated by the probe 27. For instance, in the previously cited example of actuation of the strip numbered 069, current will flow from the hundreds coding unit 39 through the individual line 35-41 corresponding to a zero hundreds digit, from the tens coding unit 49 through the individual line 36-6 corresponding to the six tens digit and from the units coding unit 41 through the individual line 37-9 corresponding to the nine units digit.

Referring now to FIG. of the accompanying drawings, it will be noted that the tens coding unit 49 shown therein includes four blocks of diodes 811, 81, 112 and 113. The transfer lines 36-@ to 36-9 extend to the coding unit 411 from appropriate ones of the panel boards, such as panel board 70, of the decoding unit 34, being connected to the diodes of such panel boards in the manner already described herein. Each of the coding units 39, 40 and 41 has four output lines 42-1, 42-2, 42-4 and 42-11; 43-1, 43-2, 43-4 and 43-3; and 44-1, 44-2, 44-4 and 44-8 respectively which extend to respective ones of the hundreds, tens and units shift registers 45, 4b and 47. In the particular system illustrated in FIG. 3, all the lines 42-1, 42-2, 42-4 and 42-3; 43-1, 43-2, 43-4 and 43-3; and 44-1, 44-2, 44-4 and 44-13 from respective ones of the shift registers 45, 46 and 47 are normally energized in their binary l conditions. The lines 42, 43 and 44 are, however, selectively de-energized or switched to their binary O condition by the series flow of current through respective ones of the coding units 39, 4t) and 41 and through the decoding unit 34. For example, in the previously mentioned case of the strip 11 numbered 069' being actuated by the probe 27, the diode 722-069 on the panel board 711 of the decoding unit 34 permits the flow of current through the tens transfer line 36-45 for the tens 6 digit. From FIG. 5, it will be seen that, as a result, current will flow through diodes 139-15 and 83-4 so de-energizing output lines 42-11 and 42-3 and leaving output lines 42-2 and 42-4 thereof energized. Consequently, the binary coded signal transmitted from the coding unit 49 to the tens shift register 46 will be 0110 corresponding to the tens digit ofb.

The transfer lines 42, 43 and 44 extending from the coding units 39, 40 and 41 respectively to the shift registers 45, 46 and 47 respectively are as already explained also connected to the display unit 51 which is in turn operative to provide a visual display of the value or identity of the strip 11 actually actuated by the probe 27, i.e., to provide a visual display of the number 1169.

As already explained, the main logic unit 53 is operative to control the transfer of the binary coded decimal values from the shift registers 45, 46 and 47 sequentially to the tape punch unit 36. Considering once again the hereinbefore mentioned example of actuation of the strip 11 numbered @159, the binary digits tllllld, 0110 and 111111 corresponding respectively to the decimal digits 1), 6 and 9 of the number 069 will be transferred sequentially to the tape punch unit 56 and suitably recorded on the tape as 911119-01 111-19111 The punched tape output 62 from the punch tape unit 56 is fed when appropriate to the digital computer 64 which is programmed to provide an output including the required data pertaining to the sample evaluated by the automatic analyzer 32. It will be understood that the automatic analyzer 32 will nonnally be operated sequentially to analyze a number of samples. The result or results for each such sample will be recorded by the chart recorder 31 and the chart or graph so obtained will normally be manually transferred to the recordreading station 33. At the record-reading station 33, the operator identifies and reads appropriate measurement positions on such charts or records. Such positions may, for example, be the peaks or troughs of curves on such charts. Operation of the decoding unit 34, of the coding units 39, 4 9 and 41, of the shift registers 43, 415 and 47, and of the tape punch unit 54 may then talre place automatically as the probe electrode 29 sequentially touches the respective underlying elements of the panel structure 14) for the various measurement positions on the chart. Alternatively the operator may be required to actuate a foot control or other switch (not shown) to initiate the transfer of the binary coded decimal signals from the shift registers 45, 46 and 47 to the tape punch unit 5b.

Other variations and modifications in the system shown in FIGS. 3, 4 and 5 are also possible without departing from the scope of the invention. For example, the invention is not restricted to systems in which the identity of each of the strips 11 which is engaged by the probe electrode 29 is first decoded into individual decimal digits which are then separately coded into binary form for sequential transfer to the tape punch unit. It is, for example, equally within the scope of this invention to code the identity of the actuated one of the metal strips 11 directly into pure binary form. This last mentioned alternative will, however, generally be contra-indicated unless the total number of the strips 11 in the panel structure 19 is itself sufficiently small that the binary coded numbers of all such strips are sufficiently short to permit their processing by the main logic unit 53 and their recording by the punch tape unit 56.

Although the invention has hereinbcfore been particularly described with reference to the use of the punch tape unit 5s, it should perhaps be stressed that the outputs of the coding units 39, 49 and 41 may be recorded in other ways. For example, such data may, as already indicated, be recorded on punch cards or on incremental magnetic tape. Alternatively, the output from the main logic unit 53 may be fed to a communication system for computer processing at a remote location.

Since the system already described with particular reference to FIG. 3 of the accompanying drawings is primarily intended to avoid the need for an on-line computer coupled directly to the automatic analyzer 32, the digital computer 44 will frequently be one which is available on a shared-time basis. One particularly important advantage of the present invention is that it permits the computer processing of analogue records from automatic analyzers without requiring an on-line computer. This is especially important for small laboratories where the cost of an on-line computer would be prohibitive.

Although the invention has hereinbefore been described with particular reference to its use in hospital laboratories, it will be understood that it is equally applicable for use in industrial and in other research and control laboratories.

It should further be explained that, although the invention has been described with reference to FIGS. 1 and 2 showing a record-reading panel structure including metal strips adapted actually to be contacted by the probe electrode 29, it is also within the scope of this invention to resort to other means of actuating a particular one of a plurality of individual probe-actuable elements underlying a record or chart at the recordreading station 33. Such actuation can, for example, be effected by a probe which is positioned on such a chart in the desired position thereon without actually piercing or perforating that chart, the proximity of the probe affecting an electrical capacitance parameter thereby effectively actuating a respective one of the strips 11. Alternatively, the individual probe-actuable elements of the record-reading panel structure can be constructed so as to be pressure-actuated by the pressure of a probe applied to a record or chart disposed on such a structure. Other possibilities will be readily apparent to those skilled in the art.

It should also be noted that it is within the scope of this invention to construct a record-receiving panel structure in accordance therewith other than by clamping together individual strips as hereinbefore described. It is, for example, within the scope of this invention to manufacture panel structures by the techniques conventionally used for the manufacture of printed circuits.

It must further be noted that the invention is in no way restricted to record-reading panel structures such as the panel structure 10 in which the probe-actuable members are all of identical dimensions and spacings. It might in fact in many circumstances be advantageous to construct the record-reading 1 panel structure with non-uniform element dimensions and spacings. Such a structure is illustrated schematically in FIG. 6 of the accompanying drawings.

The record-reading panel structure generally indicated at 85 in FIG. 6 corresponds generally to the panel structure 10 shown in FIGS. 1 and 2 in that it includes a plurality of alternating metal strips and insulating strips which are clamped in an assembled and stacked configuration by electrically insulating rods 86 and end nuts 87. Flanges 88 and 89 are similarly provided for allowing a record or chart (not shown) to be positioned correctly on the panel structure 85.

The panel structure 85 differs from the panel structure 10, however, in that the metal strips and the intervening insulating strips thereof are of several different thicknesses. In particular, it will be noted that such strips are disposed in three separate blocks or sets indicated generally at 90, 91 and 92. In the block 90, each of the metal strips 93 and each of the alternate insulating strips 94 has a thickness of x units. In the block 91, each of the metal strips 95 and the alternate insulating strips 96 has a thickness of 1.51 units whilst, in the block 92, each of the metal strips 97 and each of the alternate insulating strips 98 has a thickness of 2x units.

In the use of the panel structure 80, the record-reading resolution is greatest for those portions of a chart or record disposed over the block 90 and least for those parts of the chart disposed over the block 92. In this way, the resolution obtained by the use of such a panel structure can be designed as required for any particular application. Considerable benefit can also be obtained by providing the panel strips with logarithmic dimensions and spacings.

A further possibility in accordance with this invention is to utilize a record-receiving panel structure thereof as a recordreading x-y digitizer. For such a purpose, a panel, such as the panel 10 hereinbefore described, is first utilized as already explained to provide a sequence of output signals corresponding to the y-coordinates of the selected points on the record or chart. The chart is then removed from the panel structure and turned through ninety degrees and repositioned on that panel structure. The previously entered points on the chart are then entered a second time in precisely the same manner and usually in the same sequence to provide a second sequence of output signals corresponding to the x-coordinates of the selected points on the chart.

The method of the invention will now be further and more particularly described in the following examples which give typical results obtained by the application of the system illustrated with reference to FIGS. 1 to 5 of the accompanying drawings.

EXAMPLE 1 The panel board structure 10 shown in FIGS. 1 and 2 of the accompanying drawings was used in the overall system shown in FIG. 3 for the reading of record charts obtained by the use of an automatic analyzer for the determination of the estrogen contents of samples of human urine. The charts obtained from the automatic analyzer included two peaks for each sample, the two peaks corresponding to two representative wavelengths.

In the conventional method for determining estrogen levels from such charts, the heights of the two peaks for each sample are measured and the estrogen contents are calculated by reference to a calibration curve and a base line value obtained by analyzing standard samples at the beginning and end of the analyses of the test samples. Such a manual calculation requires approximately 4 to 5 minutes for each sample and it will be understood that, by operating the analyzer 32 at a rate of a hundred samples per day, one technician would be fully 5 occupied performing such calculations. In a typical manual operation, technician errors were found to be significant for about 8 per cent of the samples analyzed. The risk of such errors is high due to factors such as boredom. Additionally, such a technician in actually calculating results is basically performing a relatively unskilled operation in which his experience and skills are significantly wasted.

In using the system of the invention for the same purpose, it was found that it took a technician a total time of about five minutes to read the two peaks for each of the hundred samples. A further 5 minutes of the technicians time was required for calling the computer and for feeding in the punched tape record 62. The processing of the tape by the computer required about ten minutes of computer time during which time the technician was, in fact, free for other tasks. It will be noted that the technician time required for the record evaluation operation is reduced from some 400 to 500 minutes to about minutes by the use of this invention. The very substantial reduction in costs will be readily appreciated.

2 Additionally, errors, which as already explained amounted to some eight per cent in the totally manual operation, were practically completely eliminated by the use of the method of the invention.

EXAMPLE 2 The system shown in FIG. 3 of the accompanying drawings was used for the detennination of uric acid contents in samples of human blood serum. The analyses were first made operating the automatic analyzer 32 at a speed of 40 samples per hour. A second operation of the system was then carried out with a duplicate set of 20 samples, but operating at a rate of 70 samples per hour. Standard samples were also evaluated at the two analysis rates and the computer program was modified to correct the results from the second set for the increased sample interaction or carry-over resulting from the higher rate of operation.

The results obtained from the 40 sample/hour run and those from the 70 sample/hour run, with and without such computer correction, are shown in Table I.

TABLE I Computer correction of inter-sample carry-over in the determination of uric acid contents in human blood serum Uric acid (mg/100 ml.)

Test

Analysis Rate Sample 40 samples/hour 70 samples/hour 70 samples/hour Number uncorrected corrected l 6.6 6.9 6.5 2 13.6 14.0 13.7 3 3.0 3.8 3.0 4 5.4 5.7 5.5 5 7.6 7.8 7.5 6 8.6 9.0 8.6 7 5.8 6.2 5.7 8 6.8 7.2 6.9 9 3.0 3.4 3.0 10 8.6 8.8 8.6 11 5.4 5.9 5.4 12 7.6 7.8 7.6 7o 13 8.6 9.0 8.6 14 7.1 7.5 7.0 15 6.4 6.7 6.3 l6 2.0 2.4 2.0 17 3.8 4.0 3.9 18 6.0 6.2 5.9 19 7.9 8.2 7.8 20 10.0 10.3 9.8

ill

The effectiveness of the computer correction function will be readily apparent on examination of the results of Table I.

What I claim is:

l. A digitizing and record-reading system for providing a digitized output signal indicative of a value of an analogue record, which system comprises a record-receiving panel structure for receiving said analogue record in a predetermined position thereon and including in turn a plurality of mutually isolated probe-actuable elements, each of which can have an actuated or a non-actuated condition; a probe adapted manually to be applied to said analogue record on said record-receiving panel structure in said predetermined position thereon to cause actuation of an underlying and individual one of said probe-actuable elements; a decoding unit adapted to provide a digitized output signal indicative of the identity of an instantaneously actuated one of said probe-actuable elements on manual application to said analogue record of said probe; and a plurality of signal transfer means extending from individual ones of said probe-actuable elements to said decoding unit.

2. A digitizing and record-reading system as claimed in claim 1 in which said probe-actuable elements comprise a plurality of mutually parallel and electrically conductive elements electrically insulated from each other, in which said probe comprises a manually operable probe electrode adapted to pierce said analogue record for electrical contact with an underlying and individual one of said electrically conductive elements in turn to cause actuation of said underlying and individual one of said electrically conductive elements, and in which each said signal transfer means comprises an electrical conductor operatively connecting an individual one of said electrically conductive elements to said decoding unit.

3. A digitizing and record-reading system as claimed in claim 2 in which said record-receiving panel structure includes an electrically insulating record-receiving planar surface and in which each said electrically conductive element has an exposed surface disposed inwardly of said electrically insulating record-receiving planar surface of said panel structure to permit penetration of said analogue record by said probe electrode for actuation of said underlying and individual one of said electrically conductive elements thereby.

4. A digitizing and record-reading system as claimed in claim 3 in which said electrically conductive elements comprise electrically conductive strips separated by electrically insulating strips to form a stacked structure and which panel structure additionally includes clamping means retaining said electrically conductive strips and said electrically insulating strips in assembled configuration.

5. A digitizing and record-reading system as claimed in claim 4 in which each electrically conductive strip projects outwardly beyond said electrically insulating strips to facilitate electrical connection to said electrically conductive strips by said electrical conductors extending to said decoding unit.

6. A digitizing and record-reading system as claimed in claim 1 in which said electrically conductive elements are dimensioned and disposed so as to provide a varying recordreading resolution at different positions on said analogue record.

7. A digitizing and record-reading system as claimed in claim l which additionally comprises a display unit operatively coupled to said decoding unit and adapted to provide an instantaneous visual display indicative of the identity of said instantaneously actuated one of said probe-actuable elements.

ti. A digitizing and record-reading system as claimed in claim l which additionally comprises a recording unit operatively associated with said decoding unit and adapted to provide a record of the identity of said instantaneously actuated one of said probe-actuable elements.

9. A digitizing and record-reading system as claimed in claim 8 in which said recording unit includes a device operative to provide a digital record in a form suitable for subseiiuent use as an input to a di ital computer. I 0. A digitizing and recor 'reading system as claimed in claim 9 in which said recording unit is operative to provide a recorded digitized output signal indicative of the identity of an instantaneously actuated one of said probe-actuable elements in a sequentially recorded and binary coded decimal form.

lll. A method for reading and digitizing a value of an analogue record which method comprises the steps of disposing said analogue record in a predetermined position on a record-receiving panel structure including a plurality of individual and separate probe-actuable elements, each of which has an actuated and a non-actuated condition; applying a probe to said analogue record at a desired position thereon to actuate a corresponding individual one of said probe-actuable elements to cause said corresponding individual one of said probe-actuable elements to adopt said actuated condition thereof; and identifying said corresponding individual one of said probe-actuable elements by virtue of said actuated condition thereof.

12. A method as claimed in claim 111 which comprises sequentially applying said probe to said analogue record at a plurality of positions thereon and sequentially identifying the corresponding individual ones of said probe-actuable elements by virtue of the resulting actuated conditions thereof.

13. A method as claimed in claim l2 which comprises the additional step of sequentially recording the identities of said corresponding individual ones of said probe-actuable elements.

M. A method as claimed in claim B3 in which said identities of said corresponding individual ones of said probe-actuable elements are recorded as a digital record in a form suitable for subsequent use as an input to a digital computer.

15. A method as claimed in claim M in which the identification of each of said corresponding individual ones of said probe-actuable elements is effected into multi-digit decimal form, and in which each multi-digit decimal is converted into binary coded decimal form and subsequently recorded.

16. A method as claimed in claim M which additionally comprises effecting a digital computer processing operation on the data of said digital record to provide a computer readout indicative of a sequence of values of a parameter of said analogue record.

17. A method as claimed in claim 16 which additionally comprises programming said digital computer in accordance with the value of at least one parameter on which the values of said analogue record are inherently dependent. 

1. A digitizing and record-reading system for providing a digitized output signal indicative of a value of an analogue record, which system comprises a record-receiving panel structure for receiving said analogue record in a predetermined position thereon and including in turn a plurality of mutually isolated probe-actuable elements, each of which can have an actuated or a non-actuated condition; a probe adapted manually to be applied to said analogue record on said record-receiving panel structure in said predetermined position thereon to cause actuation of an underlying and individual one of said probe-actuable elements; a decoding unit adapted to provide a digitized output signal indicative of the identity of an instantaneously actuated one of said probe-actuable elements on manual application to said analogue record of said probe; and a plurality of signal transfer means extending from individual ones of said probe-actuable elements to said decoding unit.
 2. A digitizing and record-reading system as claimed in claim 1 in which said probe-actuable elements comprise a plurality of mutually parallel and electrically conductive elements electrically insulated from each other, in which said probe comprises a manually operable probe electrode adapted to pierce said analogue record for electrical contact with an underlying and individual one of said electrically conductive elements in turn to cause actuation of said underlying and individual one of said electrically conductive elements, and in which each said signal transfer means comprises an electrical conductor operatively connecting an individual one of said electrically conductive elements to said decoding unit.
 3. A digitizing and record-reading system as claimed in claim 2 in which said record-receiving panel structure includes an electrically insulating record-receiving planar surface and in which each said electrically conductive element has an exposed surface disposed inwardly of said electrically insulating record-receiving planar surface of said panel structure to permit penetration of said analogue record by said probe electrode for actuation of said underlying and individual one of said electrically conductive elements thereby.
 4. A digitizing and record-reading system as claimed in claim 3 in which said electrically conductive elements comprise electrically conductive strips separated by electrically insulating strips to form a stacked structure and which panel structure additionally includes clamping means retaining said electrically conductive strips and said electrically insulating strips in assembled configuration.
 5. A digitizing and record-reading system as claimed in claim 4 in which each electrically conductive strip projects outwardly beyond said electrically insulating strips to facilitate electrical connection to said electrically conductive strips by said electrical conductors extending to said decoding unit.
 6. A digitizing and record-reading system as claimed in claim 1 in which said electrically conductive elements are dimensioned and disposed so as to provide a varying record-reading resolution at different positions on said analogue record.
 7. A digitizing and record-reading system as claimed in claim 1 which additionally comprises a display unit operatively coupled to said decoding unit and adapted to provide an instantaneous visual display indicative of the identity of said instantaneously actuated one of said probe-actuable elements.
 8. A digitizing and record-reading system as claimed in claim 1 which additionally comprises a recording unit operatively associated with said decoding unit and adapted to provide a record of the identity of said instantaneously actuated one of said probe-actuable elements.
 9. A digitizing and record-reading system as claimed in claim 8 in which said recording unit includes a device operative to provide a digital record in a form suitable for subsequent use as an input to a digital computer.
 10. A digitizing and record-reading system as claimed in claim 9 in which said recording unit is operative to provide a recorded digitized output signal indicative of the identity of an instantaneously actuated one of said probe-actuable elements in a sequentially recorded and binary coded decimal form.
 11. A method for reading and digitizing a value of an analogue record which method comprises the steps of disposing said analogue record in a predetermined position on a record-receiving panel structure including a plurality of individual and separate probe-actuable elements, each of which has an actuated and a non-actuated condition; applying a probe to said analogue record at a desired position thereon to actuate a corresponding individual one of said probe-actuable elements to cause said corresponding individual one of said probe-actuable elements to adopt said actuated condition thereof; and identifying said corresponding individual one of said probe-actuable elements by virtue of said actuated condition thereof.
 12. A method as claimed in claim 11 which comprises sequentially applying said probe to said analogue record at a plurality of positions thereon and sequentially identifying the corresponding individual ones of said probe-actuable elements by virtue of the resulting actuated conditions thereof.
 13. A method as claimed in claim 12 which comprises the additional step of sequentially recording the identities of said corresponding individual ones of said probe-actuable elements.
 14. A method as claimed in claim 13 in which said identities of said corresponding individual ones of said probe-actuable elements are recorded as a digital record in a form suitable for subsequent use as an input to a digital computer.
 15. A method as claimed in claim 14 in which the identification of each of said corresponding individual ones of said probe-actuable elements is effected into multi-digit decimal form, and in which each multi-digit decimal is converted into binary coded decimal form and subsequently recorded.
 16. A method as claimed in claim 14 which additionally comprises effecting a digital computer processing operation on the data of said digital record to provide a computer read-out indicative of a sequence of values of a parameter of said analogue record.
 17. A method as claimed in claim 16 which additionally comprises programming said digital computer in accordance with the value of at least one parameter on which the values of said analogue record are inherently dependent. 